Modeling and simulation of an emulsion copolymerization process

Radical emulsion copolymerization is one of the most widely diffused processes aimed to produce paints easy to use because of their low viscosity. At industrial scale, such processes require a high control level of all the operating variables. Particularly, the repeatability of an emulsion polymerization process within narrow limits is one of the most desirable features because it allows for controlling also other important product qualities as final solids content, average particle size, latex viscosity and polymer average molecular weight. Other important full plant requirements are the minimization of reactants dosing times and the preparation of a latex at the highest possible concentration. In this work, the first step of a complex industrial copolymerization process has been considered. Since different monomer types (butyl acrylate, styrene, acrylic acid and acrylamide) are involved, it has been necessary to propose a complete set of rate constants for all the traditional steps of the radical emulsion reactions chain (i.e. initiation, propagation, radicals termination, backbiting and long-chain branching, micelles seeding, etc..). These parameters have then been inserted into a system of ordinary differential equations expressing all balances and control actions aimed to simulate the full plant synthesis. Finally, the proposed model has been experimentally validated through the comparison with a reaction calorimetry test carried out in an indirectly cooled semibatch reactor (RC1, 1L, Mettler Toledo). Obtained results have confirmed the reliability of the theoretical model

Integrated early warning surveillance. Achilles′ heel of one health?

Emerging and re-emerging infectious diseases and zoonoses indicate the importance of the One Health (OH) approach for early warning. At present, even when surveillance data are available, they are infrequently timeously shared between the health sectors. In the context of the MediLabSecure (MLS) Project, we investigated the collection of a set of surveillance indicators able to provide data for the implementation of integrated early warning systems in the 22 MLS countries of the Mediterranean, Black Sea and Sahel regions. We used an online questionnaire (covering vector, human, and animal sectors), focusing on seven relevant arboviruses, that was submitted to 110 officially appointed experts. Results showed that West Nile virus was perceived as the most relevant zoonotic pathogen, while Dengue virus was the most relevant non-zoonotic pathogen in the study area. Data collection of early warning indicators is in place at a different level for all the investigated pathogens and in almost all the MLS Countries. Further assessments on the reliability of the collection in place and on the feasibility of piloting an integrated early warning system for arbovirus could verify if integrated early warning really represents the Achilles’ heel of OH

Non-Markovian decay and dynamics of decoherence in private and public environments

We study the decay process in an open system, emphasizing on the relevance of the environment's spectral structure. Non-Markovian effects are included to quantitatively analyze the degradation rate of the coherent evolution. The way in which a two level system is coupled to different environments is specifically addressed: multiple connections to a single bath (public environment)or single connections to multiple baths (private environments). We numerically evaluate the decay rate of a local excitation by using the Survival Probability and the Loschmidt Echo. These rates are compared to analytical results obtained from the standard Fermi Golden Rule (FGR) in Wide Band Approximation, and a Self-Consistent evaluation that accounts for the bath's memory in cases where an exact analytical solution is possible. We observe that the correlations appearing in a public bath introduce further deviations from the FGR as compared with a private bath.Comment: 18 pages, 7 figures. Accepted for publication in Physical Review

Europe as a multilevel federation

Peer reviewedPublisher PD

EpiSouth: a network for communicable disease control in the Mediterranean region and the Balkans

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Kidins220/ARMS interacts with Pdzrn3, a protein containing multiple binding domains.

We report the identification of a novel partner of Kidins220/ARMS (Kinase D-interacting substrate of 220 kDa/Ankyrin Repeat-rich Membrane Spanning) an adaptor of neurotrophin receptors playing crucial roles during neurogenesis. Screening a phage display library of brain cDNA products we found that D. rerio Pdzrn3, a protein containing RING-finger and PDZ-domains, interacts with Kidins220/ARMS through its first PDZ-domain. Both zebrafish proteins share high homology with the corresponding mammalian proteins and both genes are developmentally expressed in neural districts where early neurogenesis occurs. The interaction was also confirmed by biochemical assays and by co-localization at the tips of growing neurites of PC12 cells induced with nerve growth factor

Zebrafish patient-derived xenografts identify chemo-response in pancreatic ductal adenocarcinoma patients

It is increasingly evident the necessity of new predictive tools for the treatment of pancreatic ductal adenocarcinoma in a personalized manner. We present a co-clinical trial testing the predic-tiveness of zPDX (zebrafish patient-derived xenograft) for assessing if patients could benefit from a therapeutic strategy (ClinicalTrials.gov: XenoZ, NCT03668418). zPDX are generated xenografting tumor tissues in zebrafish embryos. zPDX were exposed to chemotherapy regimens commonly used. We considered a zPDX a responder (R) when a decrease ≥50% in the relative tumor area was reported; otherwise, we considered them a non-responder (NR). Patients were classified as Responder if their own zPDX was classified as an R for the chemotherapy scheme she/he received an adjuvant treatment; otherwise, we considered them a Non-Responder. We compared the cancer recurrence rate at 1 year after surgery and the disease-free survival (DFS) of patients of both groups. We reported a statistically significant higher recurrence rate in the Non-Responder group: 66.7% vs. 14.3% (p = 0.036), anticipating relapse/no relapse within 1 year after surgery in 12/16 patients. The mean DFS was longer in the R-group than the NR-group, even if not statistically significant: 19.2 months vs. 12.7 months, (p = 0.123). The proposed strategy could potentially improve preclinical evaluation of treatment modalities and may enable prospective therapeutic selection in everyday clinical practice

Polaron Variational Methods In The Particle Representation Of Field Theory : I. General Formalism

We apply nonperturbative variational techniques to a relativistic scalar field theory in which heavy bosons (``nucleons'') interact with light scalar mesons via a Yukawa coupling. Integrating out the meson field and neglecting the nucleon vacuum polarization one obtains an effective action in terms of the heavy particle coordinates which is nonlocal in the proper time. As in Feynman's polaron approach we approximate this action by a retarded quadratic action whose parameters are to be determined variationally on the pole of the two-point function. Several ans\"atze for the retardation function are studied and for the most general case we derive a system of coupled variational equations. An approximate analytic solution displays the instability of the system for coupling constants beyond a critical value.Comment: 33 pages standard LaTeX, 3 uuencoded gzipped postscript figures embedded with psfig.st